Current-controlling device for electric circuits.



. e. BURNHAM. UUBBBNT com'RoLLING DEVICBFOR ELECTRIC cmcvi''.

APPLICATION FILED Nov. 9, '1910. Patented Jan. 1 2, 19,15.-

y Y I v Elms-SH BT l ,fn/6712024;

#@@m l f MQW y f .miren 'snarns rar simens;angssncrinsnrrs, ssrn-Non To' fs; in.' comtm, Bestron, MASSACHUSETTS;

i eigenen, a gnnnnnnm orl f' 'l\[assachusetts, have invented 'iinrflmprovelment' infICurrent-Controlling De ices o.rEl'ectric Circuits, of which the foltlowing-is*aspecilcation;

This invention-relates to current-control- 'ling deyieesror Velectric'-circuits, whereby any n);encessoffcurrent above a maximum demand `r-willlbe:visuallyindicated. Such a device is especially adaptedf-for use in electric-lightingisystems forflimiting the number of lamps n sedfat any fg'iven time by a consumer, ljvho is .paying afli'at-rate for a given num- Iand Stat l'rit@immediately"becomes effective.; VIn' the first preferred embodiment of my invention fa1etransfornier 71s employed as a means of -settingiupanelectro-motive force in oppo 'rl'siti'ongto :i the Vintagel of thel supplycurrent,

. 401gtiveiwlrenthe demand iseXceeded 'and said .ifmansgkis preferal'ly but not necessarily' "faidapjtedvto'continuously include said transiformer rrzrotherwise render'it .operative f'whi'l'e Ythexfdern'and isa exceeded and to return 4555i() liornialfassoonffas the exceededdemand ceases. 4

Figure',Y is fafron-t View of a current-con` 4Ntr'olili'ngz device fori electric-circuits embody- Lf'ing.fthisvinvention;ueFigs. 2, 3 and L are V firent -view sf 2- of :iniodiied forms of fcurrentV cont'rollingQ-,deVCesmhOdying this inven* Referringto Fig.l 15 a, b, represent the two lsupply?Wires-fof an:` electric -vcircuitl and 'c B5 the-lamps or othe" trically-controlled switch is employed. 'sh-mim; in' Fig. 1, said switch -consists essen `ti-allyfof asWitch-plate e, nornmily/"engaging 4a pair'of contacts e', e?, which is movable to vnected in the supplyfcircnt.

eindzneansare provided .for lincluding said' -i-:Strdnsformer'or otherwise rendermg 1t oper#A .-anslating-devices"which f `aplslica'nii; filed 'Nvmber 9,1910. seriai au. 591,410.

are vconn'eci vin said circuit in any usual*4 or suitablemanner.v v Y A transformer,` Which forms the essential element of the curentfcontrlling device, in said ligure' comprises' a" laminated jor "other forni vof core d,- having arranged thereon the primary coil d, and the secondary --coi l' d2.

Said transformer isdesigned 4to he connected 1n circult wlth the translating` 'de-,"jv'sces,` "so,A

that the supply-current Wil1. jpass through it, whereby the voltage of the supplyecurrent is opposed to ysuch an extent'asto'reducevthe potential o i' the currentl passing to the trans lating-devlces, 'andin icase'said translating-y v devices are lamps, to correspondingly rediice their brlliancy As shown'fin-.Fig.- 1., thefsecondary coil is adapted to be connected in series'relation in one of the supplycircuit Wires,y and the l "primary coil 'is adaptedto befconnected in circuit Wi1'es,.'bo th at the supply-side of the tran's'- loting-devices'; and lfor the purpose of thus connecting said coils in the'circuit an clccmultiple betiveen they two fsupplydisengagefsaid 'contacts and to engage auf 'other pair of contacts 63,' e4, and asolcno'id, v the-'movable core orarmature espi which is connected with said switch-platefor moving I it, the coil e6 of which 'is adapted to lbeconV `The transformer and electrically-emr trolled switchjmaybefconnected in the'cirfy .cuit'invarious ways';'and in Figui. the see'- vonda'ryvcoil d2 is arranged in a circuit-ire 'leading from the supply-wire a, at f, toa point-of junction f2 fromwliich a circuit-V 'Wire 'f5 leads to the supply-Wire a ntf, and the pair of contacts e. e2, are arranged in circuitlwires f8, f, leading from the supply Wire-'a at f" to the junction point f2, fand when the switch-plate e is in its normal position'said secondary coil is shin-t-c'ircuited;Y

and when moved to disengnge the contacts 'e,` e2, said secondary coil' is in seriesrelation. in the circuit and the solenoid-coil e is arranged in said circuit Wire f5 WhiiChleads `from the junction point fg'tothe 'supply oircuit-Wire a, at A 1f-pso that' saidsoenoid coil ,is at all times-in'series relationin the circuit and in series with the secondary colle?l when l the switchl 3,".2'?, fopen. an;

ranged the'supply-current"divides at f', a' partpassing through'the secondary coil to the junction point f2 and .a part passing through the switch-contactsto the junction point f2, and the whole passing through the solenoid-coil e6.

The primary-coil d` is arranged in a cir# ycuit-wire f7 leading from the supply-wire b.v

at fs to the circuit-wire f3 which includes the pair of switchcontacts c3, et, and as the switch-plate is vnormally in engagement with the other pair of switch-contacts the circuit ofsaid primary-coil is normally open, but when' closed by a movement of the switchplate saidcoil is connected in multiple between the supply-wires a and b.

As the lamps c are turned on the current will pass through the short-circuited sec# ondary-coil and the soleii'oidcoil, and said solenoid-coil is niiuenced by it, and as soon asthe demand is exceeded by the turning on 1 of more lights than the maximum demand the armature yg is pii'oted at g, which is calls or'the armature or core of said solenoidv will be drawn up or attracted, and the switch-plate moved out of engagement with the contacts e', et. and into engagement with the contacts e3, c4. lnuch 4movement of the switch-plate opens the short-circuit of the secondary-coill andcloses the circuit ofthe primary coil, so that all the current ,passes through the secondary-coil, ywhich is in series with the solenoid-coil, and also the current passes through 'the primary-coil which is in multiple between the two sides of the line, and as a result the voltage of the Icurrent supplying the lamps is opposed and the potential thereby substantially'reduced,

causing the lamps to immediately become dim, and to remain dim as long as this condition preiails. Then one or more of the lamps lare turned orf, so that the demand isv vmovable toward and from the pole, which bears a switch-arii'i fr", engaging one or the other coi'itact f/` or g?, according as said armature is in its retracted or attracted position. The secondary coil g is arranged directlywin one, side, as Q, of the supplycircuit, and the primary-coil g2 is arranged in a circuit-wire h leading-from said suppiy-circuit-wirer a to; Athe l armature, and..y

thence to the switch-arm, and a circuit-wire z'leads from the contact g? to the supply-4 `,wire a, and a circuit-wire .h2 leads from-.the

contact g7 to the. supply-wire b. Normally the armature is retracted and lshort-circl'iits the primary coil, thereby vpreventingyloss ofl voltagedue. to the impedance of the secondary-coil. By short-circuiti'ng thel rimary coil-the reactance of the secon ary coil is substantially nullied, but when" the armature is attracted, as it willbe when the circuit is opened by the switch-arm andthe primary-coilconnected in multiple between .the supply-circuitl wires ci andjb, and when thus connected substantially; the.` results heretofore Vdescribed will follow,-

`e.,; lthe voltage of thecu'rrent supplying the lamps' will be opposed and the .potential thereby vcorrespondingly reduced..

Referring to vFigf, the circuit-wire demand for current is-,eXceeded, the short-y and contact g2 shown in Fig. 2, are omitted, 'I

and a backl stop'i is, arranged back'of kthe armature, so that when the armature 1s attracted the short-circuit of the primarycoil will be opened, but said primary-coil" will not be connected' in multiple between the supply-wires a and andinsuch case tlieloss of voltage due to the impedance of 'the secondary-coil isnot nullitied, and, as a' v consequence, the voltage supplying the lamps is correspondingly reduced on account .of the counter or opposing electro-motive Jf'o'rce set up by the self-induction of the secondarycoil- Y lily invention is also susceptible .of'other modifications, as for instance, in lieu of em voying a transformer as a means offintroducing an opposing'electro-motiveV force to Ireduce the potential of thecurrent, -1 may `employ a motor-generator, as shown in Fig. Ll. Y In this embodiment of my invention a, b,

vrepresent the supply-wires, and cthetranslating-devices, and j and j a motor-gener ator, the generator being connected in they snpplyewire 7i and the motor being connected in a' branch wire j? leading from the supply-wire a to a contact-member 13 ota normally open switch, another contact member .iii

of said switch beingconnected by a circuitwire y'" tothe supply-wirel Zn. jT` represents a solenoid in the supply-wire the armature of which is connected with a lswitcl'i- )late 'is for closinfr the switch of the circuit-wires y'jf", to introduce the motorgenerator when the current passing through the coil exceeds Ia predetermined amount. As soon as the motor-generator has started an opposing electro-motiyeforce is introduced which reduces the potential. This modification lmay be used in CQIIHS'OITLWthi-.

a' large number `-of lamps.

While my invention 11s here illustrated asv" v construction, it may be applied to a threey. Vmanner Well `known wire system of ordinary'construction, in a to electricians.`

'I elamc" A current-controllingdevice for a translating-circuit consisting .of a transforzne having its secondary-coil arranged in one side of the translating-circuit and normally .short-circuted and having its primary-Coil'- erranged in' an lopen circuit which when dosed connects itin multiple With the translating-cixlet, and means controlled by' a eurrent of definite value to open the shortcircuit ofthe secondary-Coil and to close the h open circuit of theprimary-eoil, whereby 1g,

,i the voltage of the current passing so *the4 translating-devices is opposed and its po tental reduced, substantially as described.

In testimony whereof, I have signed my A name to this specification, in the presence of 2e two subscribing witnesses. A

GEORGE A. BURNHAM. v "Witnesses:

A. L. HARTEN, C. C. BADEAU. 

